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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Évaluation gastrointestinale de chats présentant un comportement de pica

Demontigny-Bédard, Isabelle 04 1900 (has links)
No description available.
412

Numerical modeling and buckling analysis of inflatable structures / Modélisation numérique et analyse du flambement des structures gonflables en textiles techniques orthotropes

Nguyen, Thanh Truong 31 August 2012 (has links)
L’objectif principal de cette thèse est de modéliser en flambement des poutres pressurisées en tissu souple homogène orthotrope (THO) composite. La première partie détaille les études expérimentales qui ont été menées sur des poutres gonflables à certain niveaux de pression afin de caractériser les propriétés mécaniques du matériau et le comportement en flambement de la structure. Dans une deuxième partie, une approche analytique a été envisagée afin d’étudier le flambement ainsi que le comportement d’une poutre gonflable orthotrope. Un modèle 3D gonflables poutre orthotrope basé sur la cinématique de Timoshenko a été présenté brièvement. La charge critique a été étudiée pour différents cas de charge avec différentes conditions aux limites. Les résultats ont été confrontés aux résultats théoriques disponibles. Pour vérifier la limite de validité des résultats, la charge d’apparition des plis a également fait l’objet d’une étude pour chacun des cas. La dernière partie est consacrée à une étude linéaire et à une analyse non-linéaire du flambement de la poutre gonflable en THO composite. Le modèle éléments finis (MEF) établi ici implique un élément poutre de Timoshenko à trois-nœuds avec une continuité de type C0. Un test de convergence du maillage sur la force critique de la poutre a été réalisé par la résolution du problème aux valeurs propres. En outre, un MEF non-linéaire a été développé en utilisant la procédure itérative de quasi-Newton avec incréments de chargement adaptatif permettant le tracé pas à pas de la réponse charge-déflexion de la poutre. Les résultats ont été validés à partir d’un certain niveau de pression par des résultats expérimentaux et numériques / The main goals of this thesis are to modeling and to perform the buckling study of inflatable beams made from homogeneous orthotropic woven fabric (HOWF) composite. Three main scenarios were investigated in this thesis. The first is the experimental studies which were performed on HOWF inflatable beam in various inflation pressures for characterizing the orthotropic mechanical properties and buckling behaviors of the beam. In the second scenario, an analytical approach was considered to study the buckling and the behavior of an inflatable orthotropic beam. A 3D inflatable orthotropic beam model based on the Timoshenko's kinematics was briefly introduced: the nonlinearities (finite rotation, follower forces) were included in this model. The results were compared with theoretical results available in the literature. To check the limit of validity of the results, the wrinkling load was also presented in every case. The last scenario is devoted to the linear eigen and non-linear buckling analysis of inflatable beam made of HOWF. The finite element (FE) model established here involves a three-noded Timoshenko beam element with C0-type continuity for the transverse displacement and quadratic shape functions for the bending rotation and the axial displacement. In the linear buckling analysis, a mesh convergence test on the beam critical load was carried out by solving the linearized eigenvalue problem. In addition, a nonlinear FE model was developed by using the quasi-Newton iteration with adaptive load stepping for tracing load-deflection response of the beam. The results were validated from a certain pressure level by experimental and thin-shell FE results
413

Fluorfria återimpregneringar : en studie om konsumentprodukter för återimpregnering av textil / Fluorine-free reimpregnations

Axelsson, Filippa, Johansson, Sofia January 2017 (has links)
Varaktig vattenavvisning från engelskans Durable Water Repellents (DWR) är en kemi som appliceras på textil för att göra den motståndskraftig mot vätska. En DWR-kemi som visat sig vara till stor belastning för miljön och därför genomgått en utfasning inom industrin är fluorkarboner. Detta har lett till fluorfria alternativ och även modifierade fluorkarboner vilka det finns bristande information kring gällande risker för miljö och hälsa. I och med övergången från fluorerade DWR till de fluorfria alternativen aktualiserades frågan kring hur ”durable”, alltså motståndskraftiga mot tvätt och användning, dessa verkligen är. Detta har resulterat i ett stort utbud av konsumentprodukter för återupplivning av vattenavvisning på beklädnad i hemmamiljö. Dessa konsumentprodukter har benämnts som återimpregneringar i denna studie. Återimpregneringar kan göra att användaren förblir nöjd med beklädnaden och detta minskar i sin tur det textila avfallet. Området är outforskat och industrin vill veta mer om dessa konsumentprodukter inklusive hur det textila materialet påverkas av dem. Studien har utgått från ett kundperspektiv vid val av relevanta parametrar och på ett kreativt sätt översatt dessa till laborativa testmetoder. De parametrar som funnits med i studien har varit vattenavvisning, färgförändring, luftgenomsläpplighet samt känsla vilka har använts för analys och jämförelse mellan åtta stycken fluorfria återimpregneringar. Två etablerade appliceringstekniker, wash-in och spray-on, har undersökts på fyra olika textilier som skulle kunna representera frilufts- samt arbetskläder. Två av textilierna var av polyester och två var av polyamid. Samtliga återimpregneringar gav en ökad vattenavvisande effekt. Resultatet varierade beroende på vilket textilt material och vilken återimpregnering som användes. De övriga testmetoderna, färgförändring, luftgenomsläpplighet och böjstyvhet, visade även de liknande variationer i resultaten. Wash-in och spray-on teknikerna kunde generellt visa på statistiska skillnader. Även produkter med samma varumärke applicerade med wash-in och spray-on teknik visade skilda resultat. De laborativa testmetoderna som valts ut visade sig vara användbara verktyg för utvärdering av återimpregneringar vid textilapplicering.  Utifrån litteraturens rön och denna studies resultat har slutsatsen dragits att konsumentprodukter för återimpregnering av textil har betydande skillnader beroende av vilken DWR-kemi de består av samt textiliens konstruktion och fibersort. Det säkraste fluorfria alternativet ur miljösynpunkt tros av rapportförfattarna vara vax som klassas som en kolväteskemi, men det finns mycket kvar att utforska innan en sådan slutsats kan dras med säkerhet. Denna studie har varit ett inledande steg mot att undersöka återimpregneringar som förhoppningsvis i framtiden kan leda till ett minskat textilt avfall med minsta möjliga miljöbelastning. / The textile industry uses durable water repellents (DWR) to achieve water repellency on textiles. One of these DWR chemistries, fluorocarbons, is an environmental issue and has therefore been phased-out in the industry. This has resulted in a market where both modified fluorocarbons and fluorine-free alternatives are available and there is a lack of information about these DWR regarding health and environmental aspects. Due to the changeover from the fluorinated DWR to the non-fluorinated options, the question was raised about how durable these really are. This resulted in a wide range of do-it-yourself consumer products for the water repellency revival. These consumer products have been referred to as reimpregnations in this study. The purpose of reimpregnations is to give clothing a longer life cycle. The customer remains satisfied with the garment and this in turn reduces the textile waste. The industry wants to know more about these unexplored consumer products, including how the textile material is affected by them. A customer perspective has been the basis for selecting relevant parameters in this study, which has been creatively translated into laboratory test methods. Parameters in this study have been water repellency, color change, air permeability and fabric hand. These have been used for analysis and comparison of eight fluorine-free reimpregnations. The techniques used were wash-in and spray-on and have been investigated on four different textiles representing outdoor clothing and workwear, two made of polyester and two of polyamide. All the reimpregnations showed an increased effect in water repellency. The result varied depending on which textile material and what kind of reimpregnation that was used. The other test methods also showed variation according to these factors. Over all the wash-in and spray-on techniques showed a statistical significance. Products from the same brand applied with wash-in and spray-on techniques also showed different results. The selected laboratory test methods proved to be useful tools for evaluation of reimpregnations in textile applications. Based on the literature combined with the results from this study the conclusion has been made that reimpregnation, of textile materials, has a significant difference between DWR chemistries as well as the construction and fibre type of the textile. The safest fluorine-free option, from an environmental point of view, is believed to be wax, which is classified as a hydrocarbon chemistry, however there is much left to explore before such a conclusion can be made with certainty. This study has been an initial step towards the investigation of reimpregnations, which hopefully in the future can lead to reduced textile waste with as little environmental impact as possible.
414

A Coarse Grained Reconfigurable Architecture Framework Supporting Macro-Dataflow Execution

Varadarajan, Keshavan 12 1900 (has links) (PDF)
A Coarse-Grained Reconfigurable Architecture (CGRA) is a processing platform which constitutes an interconnection of coarse-grained computation units (viz. Function Units (FUs), Arithmetic Logic Units (ALUs)). These units communicate directly, viz. send-receive like primitives, as opposed to the shared memory based communication used in multi-core processors. CGRAs are a well-researched topic and the design space of a CGRA is quite large. The design space can be represented as a 7-tuple (C, N, T, P, O, M, H) where each of the terms have the following meaning: C -choice of computation unit, N -choice of interconnection network, T -Choice of number of context frame (single or multiple), P -presence of partial reconfiguration, O choice of orchestration mechanism, M -design of memory hierarchy and H host-CGRA coupling. In this thesis, we develop an architectural framework for a Macro-Dataflow based CGRA where we make the following choice for each of these parameters: C -ALU, N -Network-on-Chip (NoC), T -Multiple contexts, P -support for partial reconfiguration, O -Macro Dataflow based orchestration, M -data memory banks placed at the periphery of the reconfigurable fabric (reconfigurable fabric is the name given to the interconnection of computation units), H -loose coupling between host processor and CGRA, enabling our CGRA to execute an application independent of the host-processor’s intervention. The motivations for developing such a CGRA are: To execute applications efficiently through reduction in reconfiguration time (i.e. the time needed to transfer instructions and data to the reconfigurable fabric) and reduction in execution time through better exploitation of all forms of parallelism: Instruction Level Parallelism (ILP), Data Level Parallelism (DLP) and Thread/Task Level Parallelism (TLP). We choose a macro-dataflow based orchestration framework in combination with partial reconfiguration so as to ease exploitation of TLP and DLP. Macro-dataflow serves as a light weight synchronization mechanism. We experiment with two variants of the macro-dataflow orchestration units, namely: hardware controlled orchestration unit and the compiler controlled orchestration unit. We employ a NoC as it helps reduce the reconfiguration overhead. To permit customization of the CGRA for a particular domain through the use of domain-specific custom-Intellectual Property (IP) blocks. This aids in improving both application performance and makes it energy efficient. To develop a CGRA which is completely programmable and accepts any program written using the C89 standard. The compiler and the architecture were co-developed to ensure that every feature of the architecture could be automatically programmed through an application by a compiler. In this CGRA framework, the orchestration mechanism (O) and the host-CGRA coupling (H) are kept fixed and we permit design space exploration of the other terms in the 7-tuple design space. The mode of compilation and execution remains invariant of these changes, hence referred to as a framework. We now elucidate the compilation and execution flow for this CGRA framework. An application written in C language is compiled and is transformed into a set of temporal partitions, referred to as HyperOps in this thesis. The macro-dataflow orchestration unit selects a HyperOp for execution when all its inputs are available. The instructions and operands for a ready HyperOp are transferred to the reconfigurable fabric for execution. Each ALU (in the computation unit) is capable of waiting for the availability of the input data, prior to issuing instructions. We permit the launch and execution of a temporal partition to progress in parallel, which reduces the reconfiguration overhead. We further cut launch delays by keeping loops persistent on fabric and thus eliminating the need to launch the instructions. The CGRA framework has been implemented using Bluespec System Verilog. We evaluate the performance of two of these CGRA instances: one for cryptographic applications and another instance for linear algebra kernels. We also run other general purpose integer and floating point applications to demonstrate the generic nature of these optimizations. We explore various microarchitectural optimizations viz. pipeline optimizations (i.e. changing value of T ), different forms of macro dataflow orchestration such as hardware controlled orchestration unit and compiler-controlled orchestration unit, different execution modes including resident loops, pipeline parallelism, changes to the router etc. As a result of these optimizations we observe 2.5x improvement in performance as compared to the base version. The reconfiguration overhead was hidden through overlapping launching of instructions with execution making. The perceived reconfiguration overhead is reduced drastically to about 9-11 cycles for each HyperOp, invariant of the size of the HyperOp. This can be mainly attributed to the data dependent instruction execution and use of the NoC. The overhead of the macro-dataflow execution unit was reduced to a minimum with the compiler controlled orchestration unit. To benchmark the performance of these CGRA instances, we compare the performance of these with an Intel Core 2 Quad running at 2.66GHz. On the cryptographic CGRA instance, running at 700MHz, we observe one to two orders of improvement in performance for cryptographic applications and up to one order of magnitude performance degradation for linear algebra CGRA instance. This relatively poor performance of linear algebra kernels can be attributed to the inability in exploiting ILP across computation units interconnected by the NoC, long latency in accessing data memory placed at the periphery of the reconfigurable fabric and unavailability of pipelined floating point units (which is critical to the performance of linear algebra kernels). The superior performance of the cryptographic kernels can be attributed to higher computation to load instruction ratio, careful choice of custom IP block, ability to construct large HyperOps which allows greater portion of the communication to be performed directly (as against communication through a register file in a general purpose processor) and the use of resident loops execution mode. The power consumption of a computation unit employed on the cryptography CGRA instance, along with its router is about 76mW, as estimated by Synopsys Design Vision using the Faraday 90nm technology library for an activity factor of 0.5. The power of other instances would be dependent on specific instantiation of the domain specific units. This implies that for a reconfigurable fabric of size 5 x 6 the total power consumption is about 2.3W. The area and power ( 84mW) dissipated by the macro dataflow orchestration unit, which is common to both instances, is comparable to a single computation unit, making it an effective and low overhead technique to exploit TLP.
415

Compiling For Coarse-Grained Reconfigurable Architectures Based On Dataflow Execution Paradigm

Alle, Mythri 12 1900 (has links) (PDF)
Coarse-Grained Reconfigurable Architectures(CGRAs) can be employed for accelerating computational workloads that demand both flexibility and performance. CGRAs comprise a set of computation elements interconnected using a network and this interconnection of computation elements is referred to as a reconfigurable fabric. The size of application that can be accommodated on the reconfigurable fabric is limited by the size of instruction buffers associated with each Compute element. When an application cannot be accommodated entirely, application is partitioned such that each of these partitions can be executed on the reconfigurable fabric. These partitions are scheduled by an orchestrator. The orchestrator employs dynamic dataflow execution paradigm. Dynamic dataflow execution paradigm has inherent support for synchronization and helps in exploitation of parallelism that exists across application partitions. In this thesis, we present a compiler that targets such CGRAs. The compiler presented in this thesis is capable of accepting applications specified in C89 standard. To enable architectural design space exploration, the compiler is designed such that it can be customized for several instances of CGRAs employing dataflow execution paradigm at the orchestrator. This can be achieved by specifying the appropriate configuration parameters to the compiler. The focus of this thesis is to provide efficient support for various kinds of parallelism while ensuring correctness. The compiler is designed to support fine-grained task level parallelism that exists across iterations of loops and function calls. Additionally, compiler can also support pipeline parallelism, where a loop is split into multiple stages that execute in a pipelined manner. The prototype compiler, which targets multiple instances of a CGRA, is demonstrated in this thesis. We used this compiler to target multiple variants of CGRAs employing dataflow execution paradigm. We varied the reconfigur-able fabric, orchestration mechanism employed, size of instruction buffers. We also choose applications from two different domains viz. cryptography and linear algebra. The execution time of the CGRA (the best among all instances) is compared against an Intel Quad core processor. Cryptography applications show a performance improvement ranging from more than one order of magnitude to close to two orders of magnitude. These applications have large amounts of ILP and our compiler could successfully expose the ILP available in these applications. Further, the domain customization also played an important role in achieving good performance. We employed two custom functional units for accelerating Cryptography applications and compiler could efficiently use them. In linear algebra kernels we observe multiple iterations of the loop executing in parallel, effectively exploiting loop-level parallelism at runtime. Inspite of this we notice close to an order of magnitude performance degradation. The reason for this degradation can be attributed to the use of non-pipelined floating point units, and the delays involved in accessing memory. Pipeline parallelism was demonstrated using this compiler for FFT and QR factorization. Thus, the compiler is capable of efficiently supporting different kinds of parallelism and can support complete C89 standard. Further, the compiler can also support different instances of CGRAs employing dataflow execution paradigm.
416

Conception d'antennes pour le réseau BAN et modélisation du canal de propagation / BAN antennas conception and channel modelling

Alves, Thierry 01 April 2011 (has links)
Les études présentées dans cette thèse font l’objet d’un travail innovant concernant la conception des antennes pour les réseaux de type BAN et la modélisation des canaux associés. L’ouvrage de thèse est réparti en quatre chapitres. Deux chapitres sont consacrés à la modélisation de la propagation le long du corps où l’on montre que les formulations analytiques d’ondes de surface et d’ondes rampantes sont applicables dans ce contexte. L’effet des tissus adipeux est également pris en compte par le biais d’un modèle à trois couches (peau, graisse et muscle) et renseigne sur la variabilité du bilan de liaison suivant les personnes. Ce type de modélisation est le premier à inclure les formes du corps, les caractéristiques électriques des tissus biologiques et les caractéristiques de rayonnement des antennes. Une méthode basée sur l’autocorrélation du canal est également présentée afin de connaître les temps de cohérences des évanouissements lents et rapides. Par la suite, il est montré comment les évanouissements lents sont extraits par le biais d’un filtrage FFT fonction du temps de cohérence associé. L’étude des canaux se termine sur une série de mesures en chambre anéchoïde qui a permis de vérifier la validité des modèles analytiques. Des mesures en milieu indoor ont abouti à la proposition de plusieurs modèles statistiques basés sur une loi de Nakagami-m fonction de la distance sur le corps. Deux autres chapitres sont consacrés à la conception d’antennes à proximité de tissus biologiques et devant être intégrées dans des biocapteurs ou des vêtements. Pour cela, nous nous sommes particulièrement intéressés aux structures en F-inversé comme les IFA imprimées et les PIFA. Nous avons également réalisé des monopôles courts ayant un comportement de type magnétique. Nous montrons par le biais de simulations et de mesures sur un fantôme que seules les antennes du type monopôle et PIFA permettent une bonne excitation des ondes de surface. On montre par la suite l’influence du facteur de qualité d’une antenne sur son rendement et l’on en conclue qu’une antenne doit présenter un facteur de qualité faible pour avoir un bon rendement. La désensibilisation d’une antenne face au corps est également présentée. L’emploi de feuilles de ferrites aide à concentrer le champ réactif et limite ainsi les inévitables désadaptations dues au corps. Le coefficient de qualité joue également un rôle important dans le comportement de l’antenne face aux variabilités des tissus biologiques. L’estimation du rendement est un autre point difficile à réaliser lorsque les antennes sont sur le corps. Malgré tout nous proposons une nouvelle méthode que nous vérifions par simulation. Finalement, une structure à diversité est également proposée. Cette dernière tient compte des connaissances acquises au long de ce travail de recherche. Une sélection des meilleurs types d’antennes du point de vu canal et rendement est réalisée. La structure choisie est composée d’une PIFA et d’un monopôle court découplés par le biais de fentes λ/4. Des mesures in situ en milieu indoor donnent un gain en diversité maximum de 8.1 dB pour un schéma de type sélection / BAN antennas conception and channel modelling
417

Bezpečná implementace technologie blockchain / Secure Implementation of Blockchain Technology

Kovář, Adam January 2020 (has links)
This thesis describes basis of blockchain technology implementation for SAP Cloud platform with emphasis to security and safety of critical data which are stored in blockchain. This diploma thesis implements letter of credit to see and control business process administration. It also compares all the possible technology modification. Thesis describes all elementary parts of software which are necessary to implement while storing data and secure integrity. This thesis also leverages ideal configuration of each programable block in implementation. Alternative configurations of possible solutions are described with pros and cons as well. Another part of diploma thesis is actual working implementation as a proof of concept to cover letter of credit. All parts of code are design to be stand alone to provide working concept for possible implementation and can source as a help to write productive code. User using this concept will be able to see whole process and create new statutes for whole letter of credit business process.
418

Statická analýza textilních konstrukcí / Static Analysis of Textile Structures

Husáriková, Natália January 2017 (has links)
This work deals with the design and calculation of membrane structure for shelter placed above selected ground plan. The hyperbolic paraboloid was chosen as most optimal shape. Subsequently, three different sub-studies were conducted. In the first study, influence of mesh density on a finite element calculation model was studied. Second study deal with the effect of the geometry changes of the computational model. In the third study, deformations and tensions of membrane structure in relation to material formation calculation model was studied. For the static solution of those selected variant, structural analysis software RFEM and RF-FORM-FINDING add-on module was used. Geometric nonlinear solution was applied in the calculation.
419

Centrum polymerních systémů ve Zlíně - stavebně technologická příprava výstavby / Polymer Systems Centre in Zlín - the Construction Techological Planning

Foltánek, Jan January 2017 (has links)
The thesis deals with a technological project of Polymer System Centre in Zlín. It focuses on financial documentation and a time schedule of the construction. The technological project in detail focuses on implementation of a fabric of the Polymer System Centre. The thesis includes a technical report which suggests procedure of the construction. The technological documentation includes a plan of the construction site arrangement, a time schedule, a financial plan for the construction, a budget, a technological report suggesting partitions made of magnesium slabs, a control plan, a test plan and health and safety plan.
420

Le rôle des communautés religieuses dans la fabrique urbaine de Rouen (Xe-XVe siècle) / The role of religious communities in the urban fabric of Rouen (10th-15th)

Levieux, Lise 10 December 2018 (has links)
La ville de Rouen est, du 10e au 15e siècle, un centre religieux puissant. Siège de l’archevêché, cet espace accueille près d’une quinzaine de communautés religieuses et comprend trente-six églises paroissiales à la fin du Moyen Âge. Ces communautés religieuses, qui suivent une règle, doivent, au 10e siècle, s’insérer dans un espace urbain déjà formé par les multiples interactions entre la société et son environnement. L’intégration d’un complexe monastique ou conventuel doit composer avec les autres éléments constituants de la ville tels la voirie, l’habitat ou les pôles de pouvoir. La prise en compte des différentes composantes de l’espace urbain n’est pas le seul élément déterminant de l’implantation des communautés : le lieu choisi résulte également de l’observance de la communauté et du soutien de bienfaiteurs influents. La construction d’un complexe monastique ou conventuel au sein de la trame urbaine est un processus plus ou moins long impliquant l’acquisition de divers terrains et leur aménagement. Par la suite, ce complexe religieux modifie son environnement dans la longue durée que ce soit par des agrandissements successifs ou par la modification de ses abords. Cet enclos gèle une portion de l’espace urbain et s’inscrit durablement dans le parcellaire de la ville. Enfin, les communautés agissent – ou interagissent – sur tout l’espace urbain : d’une part, par leur rôle dans la formation du maillage paroissial, d’autre part par la création de secteurs urbains spécifiques ou par leurs possessions foncières. Ces différentes facettes de l’impact des communautés religieuses dans la ville de Rouen ont été étudiées à l’aide d’une base de données textuelles et d’un système d’information géographique qui permet de travailler à différentes échelles d’espace et de temps. / From the 10th to the 15th century, the city of Rouen is a powerful religious center. Seat of the archbishopric, it is home to nearly fifteen religious communities and includes thirty-six parish churches in the late Middle Ages. During the 10th century, these religious communities, who follow a rule, need to integrate an urban space already shaped by the numerous interactions between society and its environment. The integration of a monastic or conventual complex needs to reckon with the other components of the city, such as road networks, residential areas or power centers. Taking the different building blocks of the urban space into account is not the only factor determining the settlement of communities: the chosen area also depends on the observance of the community and the support of influential benefactors. The building of a monastic or conventual complex at the heart of the urban fabric is a relatively long process that requires acquiring and transforming several plots of land. Subsequently, the religious community shapes its environment in the long term whether by successive enlargements or by modifying its surroundings. This enclosure blocks part of the urban space and establishes itself firmly in the city’s parcel plan. Lastly, the communities act – or interact – all over the urban space: on the one hand through their role in the formation of the parish network and on the other hand through the creation of specific urban sectors or their land holdings. These different aspects of the impact of religious communities in the city of Rouen have been studied thanks to a textual database and a geographical information system allowing work at different scales of time and space.

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